Obama has a much more liberal profile than he did several weeks ago. Moderate, independent voters are now less sure that Obama shares their values. Hillary Clinton voters are much, much more hostile toward him. His supporters look more and more like the McGovern-Dukakis constituency, and the walls between that constituency and the rest of the country are higher than they were weeks ago.

Obama is going to have to work hard to tear down those walls over the coming months. He is going to have to work hard first to win over the Clinton voters, who are more economically populist and socially conservative than his supporters. He is also going to have to work hard to win over suburban independents, who are less economically populist than his current supporters. He's going to have to break conspicuously with orthodox liberalism to re-establish that values connection with people in Ohio and Missouri.

This will require a pivot, or at least a rediscovery of some themes that have faded into the background as the contest for partisans has grown more intense.

Can some new (or newly rediscovered) education policies and rhetoric help? Maybe. He should surely continue to channel Bill Cosby and talk about the need for parents to take responsibility for their children. (Beyond being sensible, this appeals to social conservatives.) This is a standard theme he mentions when addressing predominantly African-American audiences (themselves quite socially conservative); he should use it all the time.

As for suburban independents, his position on No Child Left Behind most likely appeals to them already, what with his talk about saving art and music and literature from the ravages of "teaching to the test." But he could go one step further and also talk about high-performing students who are being forgotten by our current education system and the need to help them achieve their potential too. (What suburban independent doesn't think that his or her own child is gifted?)

The primary season has been a disappointing one for the education issue; perhaps the general election will provide some new opportunities. And if Obama doesn't seize them, Senator McCain should.